Question: Jessica ate 1 slice of cake. Michael ate 1 slice. If Jessica ate $\dfrac{1}{3}$ of the cake, what fraction of the cake is remaining?
Explanation: If 1 slice represents $\dfrac{1}{3}$ of the cake, there must have been a total of 3 slices. $\text{fraction of cake remaining} = \dfrac{\text{number of slices remaining}}{\text{number of slices total}}$ Together they ate 2 slices, which leaves 1 out of 3 slices remaining. There is $\dfrac{1}{3}$ of the cake remaining.